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Cirrhosis of the Liver Introduction
The liver, the largest organ in the body, is
essential in keeping the body functioning properly. It removes or
neutralizes poisons from the blood, produces immune agents to
control infection, and removes germs and bacteria from the blood.
It makes proteins that regulate blood clotting and produces bile
to help absorb fats and fat-soluble vitamins. You cannot live
without a functioning liver.
In cirrhosis of the liver, scar tissue replaces
normal, healthy tissue, blocking the flow of blood through the
organ and preventing it from working as it should. Cirrhosis is
the eighth leading cause of death by disease, killing about 25,000
people each year. Also, the cost of cirrhosis in terms of human
suffering, hospital costs, and lost productivity is high.
Causes
Cirrhosis has many causes. In the United States,
chronic alcoholism and hepatitis C are the most common causes.
Alcoholic liver disease. To many people,
cirrhosis of the liver is synonymous with chronic alcoholism, but
in fact, alcoholism is only one of the causes. Alcoholic cirrhosis
usually develops after more than a decade of heavy drinking. The
amount of alcohol that can injure the liver varies greatly from
person to person. In women, as few as two to three drinks per day
have been linked with cirrhosis and in men, as few as three to
four drinks per day. Alcohol seems to injure the liver by blocking
the normal metabolism of protein, fats, and carbohydrates.
Chronic hepatitis C. The hepatitis C
virus ranks with alcohol as the major cause of chronic liver
disease and cirrhosis in the United States. Infection with this
virus causes inflammation of and low grade damage to the liver
that over several decades can lead to cirrhosis.
Chronic hepatitis B and D. The hepatitis
B virus is probably the most common cause of cirrhosis worldwide,
but in the United States and Western world it is less common.
Hepatitis B, like hepatitis C, causes liver inflammation and
injury that over several decades can lead to cirrhosis. The
hepatitis D virus is another virus that infects the liver, but
only in people who already have hepatitis B.
Autoimmune hepatitis. This type of
hepatitis is caused by a problem with the immune system.
Inherited diseases. Alpha-1 antitrypsin
deficiency, hemochromatosis, Wilson's disease, galactosemia, and
glycogen storage diseases are among the inherited diseases that
interfere with the way the liver produces, processes, and stores
enzymes, proteins, metals, and other substances the body needs to
function properly.
Nonalcoholic steatohepatitis (NASH). In
NASH, fat builds up in the liver and eventually causes scar
tissue. This type of hepatitis appears to be associated with
diabetes, protein malnutrition, obesity, coronary artery disease,
and corticosteroid treatment.
Blocked bile ducts. When the ducts that
carry bile out of the liver are blocked, bile backs up and damages
liver tissue. In babies, blocked bile ducts are most commonly
caused by biliary atresia, a disease in which the bile ducts are
absent or injured. In adults, the most common cause is primary
biliary cirrhosis, a disease in which the ducts become inflamed,
blocked, and scarred. Secondary biliary cirrhosis can happen after
gallbladder surgery, if the ducts are inadvertently tied off or
injured.
Drugs, toxins, and infections. Severe
reactions to prescription drugs, prolonged exposure to
environmental toxins, the parasitic infection schistosomiasis, and
repeated bouts of heart failure with liver congestion can each
lead to cirrhosis.
Symptoms
Many people with cirrhosis have no symptoms in
the early stages of the disease. However, as scar tissue replaces
healthy cells, liver function starts to fail and a person may
experience the following symptoms:
- Exhaustion
- Fatigue
- Loss of appetite
- Nausea
- Weakness
- Weight loss.
As the disease progresses, complications may
develop. In some people, these may be the first signs of the
disease.
Complications of Cirrhosis
Loss of liver function affects the body in many
ways. Following are common problems, or complications, caused by
cirrhosis.
Edema and ascites. When the liver loses
its ability to make the protein albumin, water accumulates in the
leg (edema) and abdomen (ascites).
Bruising and bleeding. When the liver
slows or stops production of the proteins needed for blood
clotting, a person will bruise or bleed easily.
Jaundice. Jaundice is a yellowing of the
skin and eyes that occurs when the diseased liver does not absorb
enough bilirubin.
Itching. Bile products deposited in the
skin may cause intense itching.
Gallstones. If cirrhosis prevents bile
from reaching the gallbladder, a person may develop gallstones.
Toxins in the blood or brain. A damaged
liver cannot remove toxins from the blood, causing them to
accumulate in the blood and eventually the brain. There, toxins
can dull mental functioning and cause personality changes, coma,
and even death. Signs of the buildup of toxins in the brain
include neglect of personal appearance, unresponsiveness,
forgetfulness, trouble concentrating, or changes in sleep habits.
Sensitivity to medication. Cirrhosis
slows the liver's ability to filter medications from the blood.
Because the liver does not remove drugs from the blood at the
usual rate, they act longer than expected and build up in the
body. This causes a person to be more sensitive to medications and
their side effects.
Portal hypertension. Normally, blood from
the intestines and spleen is carried to the liver through the
portal vein. But cirrhosis slows the normal flow of blood through
the portal vein, which increases the pressure inside it. This
condition is called portal hypertension.
Varices. When blood flow through the
portal vein slows, blood from the intestines and spleen backs up
into blood vessels in the stomach and esophagus. These blood
vessels may become enlarged because they are not meant to carry
this much blood. The enlarged blood vessels, called varices, have
thin walls and carry high pressure, and thus are more likely to
burst. If they do burst, the result is a serious bleeding problem
in the upper stomach or esophagus that requires immediate medical
attention.
Problems in other organs. Cirrhosis can
cause immune system dysfunction, leading to infection. Ascites
(fluid) in the abdomen may become infected with bacteria normally
present in the intestines, and cirrhosis can also lead to kidney
dysfunction and failure.
Diagnosis
The doctor may diagnose cirrhosis on the basis
of symptoms, laboratory tests, the patient's medical history, and
a physical examination. For example, during a physical
examination, the doctor may notice that the liver feels harder or
larger than usual and order blood tests that can show whether
liver disease is present.
If looking at the liver is necessary to check
for signs of disease, the doctor might order a computerized axial
tomography (CAT) scan, ultrasound, or a scan of the liver using a
radioisotope (a harmless radioactive substance that highlights the
liver). Or the doctor might look at the liver using a laparoscope,
an instrument inserted through the abdomen that relays pictures
back to a computer screen.
A liver biopsy will confirm the diagnosis. For a
biopsy, the doctor uses a needle to take a small sample of tissue
from the liver, then examines it for scarring or other signs of
disease.
Treatment
Liver damage from cirrhosis cannot be reversed,
but treatment can stop or delay further progression and reduce
complications. Treatment depends on the cause of cirrhosis and any
complications a person is experiencing. For example, cirrhosis
caused by alcohol abuse is treated by abstaining from alcohol.
Treatment for hepatitis-related cirrhosis involves medications
used to treat the different types of hepatitis, such as interferon
for viral hepatitis and corticosteroids for autoimmune hepatitis.
Cirrhosis caused by Wilson's disease, in which copper builds up in
organs, is treated with medications to remove the copper. These
are just a few examples--treatment for cirrhosis resulting from
other diseases will depend on the underlying cause. In all cases,
regardless of the cause, following a healthy diet and avoiding
alcohol are essential because the body needs all the nutrients it
can get, and alcohol will only lead to more liver damage.
Treatment will also include remedies for
complications. For example, for ascites and edema, the doctor may
recommend a low-sodium diet or the use of diuretics, which are
drugs that remove fluid from the body. Antibiotics will be
prescribed for infections, and various medications can help with
itching. Protein causes toxins to form in the digestive tract, so
eating less protein will help decrease the buildup of toxins in
the blood and brain. The doctor may also prescribe laxatives to
help absorb the toxins and remove them from the intestines.
For portal hypertension, the doctor may
prescribe blood pressure medication such as a beta-blocker. If
varices bleed, the doctor may either inject them with a clotting
agent or perform a rubber-band ligation, which uses a special
device to compress the varices and stop the bleeding.
When complications cannot be controlled or when
the liver becomes so damaged from scarring that it completely
stops functioning, a liver transplant is necessary. In liver
transplantation surgery, a diseased liver is removed and replaced
with a healthy one from an organ donor. About 80 to 90 percent of
people survive liver transplantation. Survival rates have improved
over the past several years because of drugs such as cyclosporine
and tacrolimus, which suppress the immune system and keep it from
attacking and damaging the new liver.
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